Noctua's DO line of coolers has become a default choice when it comes to quietly cooling AMD Opteron CPUs. Upgrading both compatibility and performance, the new A3 model features Noctua's professional NM-A3 SecuFirm2™ mounting system that not only supports socket G34, C32 and F, but also allows to install the cooler turned by 90°. Thanks to six heatpipes, a performance optimised fin stack and its two premium grade NF-B9 92mm fans, the compact NH-U9DO A3 cools Opteron processors up to a thermal design power (TDP) of 115W at minimum noise levels. Bundled with Noctua's industrial-grade NT-H1 thermal compound and fitting standard 4U chassis, the NH-U9DO A3 forms a complete premium quality package for quietly cooling AMD workstations and servers.

Caution: Due to its more compact design and quiet operation, the NH-U9DO A3 is approved only for processors with up to 115W thermal design power (TDP). Using the NH-U9DO A3 on higher TDP processors may be possible with increased case ventilation depending on the specific configuration but is not officially supported by Noctua.